Do you know that

共享题干题                                                                        （一）
                                                                    Step Back in Time
阅读材料，回答问题。
      Do you know that we live a lot longer now than the people who were born before us? One hundred years ago the average woman lived to be 45. But now, she can live until at least 80.
     One of the main reasons for people living longer is that we know how to look after ourselves better. We know which foods are good for us and what we have to eat to make sure our bodies get all the healthy things they need.We know why we sometimes get ill and what to do to get better again. And we know how important it is to do lots of exercise to keep our hearts beating healthily.
    But in order that we don't slip back into bad habits, let's have a look at what life was like 100 years ago.
   Families had between 15 and 20 children, although many babies didn't live long.Children suffered from lots of diseases, especially tickets (佝偻病 ) and scurvy ( 坏血病) , which are both caused by bad diets. This is because many families were very poor and not able to feed their children well.
    Really poor families who lived in crowded cities like London and Manchester often slept standing up,bending over a piece of string, because there was no room for them to lie down. People didn't have fridges until the 1920s. They kept fresh food cold by storing it on windowsills (窗台板 ) , blocks of ice, or even burying it in the garden.
   Some children had to start work at the age of seven or eight to earn money for their parents. If you had lived 100 years ago, you might well be selling matchsticks ( 火柴杆) ( a job done by many children ) or working with your dad by now.